When Pete and Ellie decide to start a family, they stumble into the world of foster care adoption. They hope to take in one small child but when they meet three siblings, including a rebellious 15 year old girl, they find themselves speeding from zero to three kids overnight.

Siblings Wednesday and Pugsley Addams will stop at nothing to get rid of Pubert, the new baby boy adored by parents Gomez and Morticia. Things go from bad to worse when the new “black widow” nanny, Debbie Jellinsky, launches her plan to add Fester to her collection of dead husbands.